Postgresql how to convert empty string to "Not Submitted"?

Question

PostgreSQL

Good afternoon! There is a selection:
select status from rezultat
It is necessary that in the status field there should be the line "Not sent" instead of an empty line, please tell me how this can be done?

Answer 1

What is an "empty string", a zero-length string, or NULL? However, both cases are covered by the construction
COALESCE(NULLIF(status, ''), 'Не отправлено')
. If there can be a handful of spaces in the status - first trim.

Answer 2

If an empty string means NULL - then COALESCE
If an empty string means "" - then CASE